Crystalline forms of (3-Amino-oxetan-3-ylmethyl)-[2-(5,5-dioxo-5,6,7,9-tetrahydro-5lambda*6*-thia-8-aza-benzocyclohepten-8-yl)-6-methyl-quinazolin-4-yl]-amine

ABSTRACT

The present invention relates to novel crystalline forms of compound (I), 
     
       
         
         
             
             
         
       
         
         
           
             (3-Amino-oxetan-3-ylmethyl)-[2-(5,5-dioxo-5,6,7,9-tetrahydro-5lambda*6*-thia-8-aza-benzocyclohepten-8-yl)-6-methyl-quinazolin-4-yl]-amine and pharmaceutical compositions comprising the crystalline forms thereof disclosed herein, which may be used for the treatment or prophylaxis of a viral disease in a patient relating to respiratory syncytial virus (RSV) infection or a disease caused by RSV infection.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a division of U.S. patent application Ser. No. 15/870,151, filed on Jan. 12, 2018, which issued as U.S. Pat. No. 10,071,999 on Sep. 11, 2018, which is a continuation of International Patent Application No. PCT/EP2016/066482, filed on Jul. 12, 2016, which claims priority to International Patent Application No. PCT/CN2015/084225, filed on Jul. 16, 2015. The entire contents of each of the above patent applications are hereby incorporated by reference.

The present invention relates to novel crystalline forms of compound (I),

(3-Amino-oxetan-3-ylmethyl)-[2-(5,5-dioxo-5,6,7,9-tetrahydro-5lambda*6*-thia-8-aza-benzocyclohepten-8-yl)-6-methyl-quinazolin-4-yl]-amine (also named as N-[(3-Aminooxetan-3-yl)methyl]-2-(1,1-dioxido-2,3-dihydro-1,4-benzothiazepin-4(5H)-yl)-6-methylquinazolin-4-amine) and pharmaceutical compositions comprising the crystalline forms thereof disclosed herein, which may be used for the treatment or prophylaxis of a viral disease in a patient relating to respiratory syncytial virus (RSV) infection or a disease caused by RSV infection.

BACKGROUND OF THE INVENTION

Respiratory Syncytial Virus (RSV) is the leading viral cause of death in children less than 5 years old and pediatric lower respiratory tract infection and infant hospitalization. Elderly and immune compromised adults are also high risk population. Currently, there is no approved vaccine on the market. Inhibitors of RSV are useful to limit the establishment and progression of infection by RSV as well as in diagnostic assays for RSV.

(3-Amino-oxetan-3-ylmethyl)-[2-(5,5-dioxo-5,6,7,9-tetrahydro-5lambda*6*-thia-8-aza-benzocyclohepten-8-yl)-6-methyl-quinazolin-4-yl]-amine (compound (I)) was disclosed in WO2013020993 as an effective respiratory syncytial virus (RSV) inhibitor. The compound (I) is also named as N-[(3-Aminooxetan-3-yl)methyl]-2-(1,1-dioxido-2,3-dihydro-1,4-benzothiazepin-4(5H)-yl)-6-methylquinazolin-4-amine.

Form D of compound (I) was found as metastable form at the early research stage and the hygroscopicity of Form D of compound (I) makes it not suitable for further drug development. As an action of risk mitigation, comprehensive studies were conducted. As one of the objections of this patent, several novel crystalline forms were synthesized and characterized, showing significantly improved hygroscopicity compared with Form D of compound (I). Meanwhile, developing novel crystalline forms of compound (I) with good stability and/or aqueous solubility are also one of the objectives of this patent respectively. These novel crystalline forms enhanced the developability of compound (I) fundamentally.

The present disclosure relates generally to novel crystalline forms of compound (I), and processes to make those forms.

SUMMARY OF THE INVENTION

The present invention relates to polymorphs, salts, co-crystals and methods for the synthesis of selective production of crystalline forms of (3-Amino-oxetan-3-ylmethyl)-[2-(5,5-dioxo-5,6,7,9-tetrahydro-5lambda*6*-thia-8-aza-benzocyclohepten-8-yl)-6-methyl-quinazolin-4-yl]-amine.

In one aspect, the crystalline form of compound (I) is Form A, Form B, Form C, Form D, Form E or Form F or a combination thereof.

In another embodiment, the crystalline form of compound (I) is Form A that exhibits an X-ray powder diffraction (XRPD) pattern with characteristic peaks expressed in degrees 2-theta at 9.79°±0.10°, 10.64°±0.10°, 16.79°±0.10°, 17.51°±0.10°, 20.12°±0.10°, 21.62°±0.10° and 25.79°±0.10°.

In a further embodiment, the crystalline form of compound (I) is Form A that exhibits an X-ray powder diffraction (XRPD) pattern with characteristic peaks expressed in degrees 2-theta at 6.46°±0.10°, 8.37°±0.10°, 9.79°±0.10°, 10.64°±0.10°, 12.91°±0.10°, 16.79°±0.10°, 17.51°±0.10°, 18.15°±0.10°, 19.65°±0.10°, 20.12°±0.10°, 21.62°±0.10°, 23.34°±0.10° and 25.79°±0.10°.

In a further embodiment, the crystalline form of compound (I) is Form A that exhibits an X-ray powder diffraction (XRPD) pattern shown in FIG. 1.

In a further embodiment, the crystalline form of compound (I) is Form A with a differential scanning calorimetry (DSC) thermogram comprising endothermic peak with onset temperature at 225.3° C.±3° C.

In another embodiment, the crystalline form of compound (I) is Form B that exhibits an X-ray powder diffraction (XRPD) pattern with characteristic peaks expressed in degrees 2-theta at 10.21°±0.10°, 11.93°±0.10°, 13.22°±0.10°, 14.35°±0.10°, 18.56°±0.10°, 20.79°±0.10°, 23.24°±0.10° and 25.15°±0.10°.

In a further embodiment, the crystalline form of compound (I) is Form B that exhibits an X-ray powder diffraction (XRPD) pattern with characteristic peaks expressed in degrees 2-theta at 10.21°±0.10°, 11.93°±0.10°, 13.22°±0.10°, 14.35°±0.10°, 15.02°±0.10°, 16.31°±0.10°, 17.66°±0.10°, 18.56°±0.10°, 20.06°±0.10°, 20.79°±0.10°, 21.42°±0.10°, 23.24°±0.10°, 25.15°±0.10°, 26.21°±0.10°, 26.74°±0.10° and 29.44°±0.10°.

In a further embodiment, the crystalline form of compound (I) is Form B that exhibits an X-ray powder diffraction (XRPD) pattern shown in FIG. 4.

In a further embodiment, the crystalline Form B is a hydrate of compound (I).

In a further embodiment, the crystalline form of compound (I) is Form B with a differential scanning calorimetry (DSC) thermogram comprising endothermic peak with dehydration temperature at 57.2° C.±3° C. and onset temperature at 256.3° C.±3° C.

In another embodiment, the crystalline form of compound (I) is Form C that exhibits an X-ray powder diffraction (XRPD) pattern with characteristic peaks expressed in degrees 2-theta at 8.41°±0.10°, 19.21°±0.10°, 20.49°±0.10°, 20.83°±0.10°, 21.69°±0.10°, 21.99°±0.10° and 22.13°±0.10°.

In a further embodiment, the crystalline form of compound (I) is Form C that exhibits an X-ray powder diffraction (XRPD) pattern with characteristic peaks expressed in degrees 2-theta at 8.41°±0.10°, 13.71°±0.10°, 14.95°±0.10°, 17.01°±0.10°, 19.21°±0.10°, 20.49°±0.10°, 20.83°±0.10°, 21.46°±0.10°, 21.69°±0.10°, 21.99°±0.10°, 22.13°±0.10°, 24.95°±0.10°, 25.85°±0.10°, 26.63°±0.10° and 27.34°±0.10°.

In a further embodiment, the crystalline form of compound (I) is Form C that exhibits an X-ray powder diffraction (XRPD) pattern shown in FIG. 7.

In a further embodiment, the crystalline form of compound (I) is Form C with a differential scanning calorimetry (DSC) thermogram comprising endothermic peak with onset temperature at 256.6° C.±3° C.

In another embodiment, the crystalline form of compound (I) is Form D that exhibits an X-ray powder diffraction (XRPD) pattern with characteristic peaks expressed in degrees 2-theta at 7.79°±0.10°, 10.18°±0.10°, 11.15°±0.10°, 12.40°±0.10°, 18.68°±0.10°, 20.43°±0.10° and 24.83°±0.10°.

In a further embodiment, the crystalline form of compound (I) is Form D that exhibits an X-ray powder diffraction (XRPD) pattern with characteristic peaks expressed in degrees 2-theta at 7.79°±0.10°, 10.18°±0.10°, 11.15°±0.10°, 12.40°±0.10°, 12.90°±0.10°, 18.68°±0.10°, 19.73°±0.10°, 20.16°±0.10°, 20.43°±0.10°, 21.16°±0.10°, 23.14°±0.10°, 23.93°±0.10°, 24.83°±0.10°, 25.71°±0.10° and 27.11°±0.10°.

In a further embodiment, the crystalline form of compound (I) is Form D that exhibits an X-ray powder diffraction (XRPD) pattern shown in FIG. 11.

In a further embodiment, the crystalline form of compound (I) is Form D with a differential scanning calorimetry (DSC) thermogram comprising endothermic peak with dehydration temperature at 53.2° C.±3° C. and onset melting temperature at 256.3° C.±3° C.

In another embodiment, the crystalline form of compound (I) is Form E that exhibits an X-ray powder diffraction (XRPD) pattern with characteristic peaks expressed in degrees 2-theta at 5.96°±0.10°, 8.32°±0.10°, 9.34°±0.10°, 11.82°±0.10°, 15.09°±0.10°, 19.44°±0.10° and 25.60°±0.10°.

In a further embodiment, the crystalline form of compound (I) is Form E that exhibits an X-ray powder diffraction (XRPD) pattern with characteristic peaks expressed in degrees 2-theta at 5.96°±0.10°, 8.32°±0.10°, 9.34°±0.10°, 11.82°±0.10°, 13.22°±0.10°, 15.09°±0.10°, 16.90°±0.10°, 17.46°±0.10°, 19.44°±0.10°, 21.08°±0.10°, 22.59°±0.10°, 23.12°±0.10°, 25.25°±0.10°, 25.60°±0.10° and 28.34°±0.10°.

In a further embodiment, the crystalline form of compound (I) is Form E that exhibits an X-ray powder diffraction (XRPD) pattern shown in FIG. 14.

In a further embodiment, the crystalline Form E is a mono acetate salt of compound (I).

In another embodiment, the crystalline form of compound (I) is Form F that exhibits an X-ray powder diffraction (XRPD) pattern with characteristic peaks expressed in degrees 2-theta at 10.27°±0.10°, 12.38°±0.10°, 18.59°±0.10°, 19.91°±0.10°, 20.14°±0.10°, 23.93°±0.10° and 24.78°±0.10°.

In a further embodiment, the crystalline form of compound (I) is Form F that exhibits an X-ray powder diffraction (XRPD) pattern with characteristic peaks expressed in degrees 2-theta at 8.32°±0.10°, 10.27°±0.10°, 12.38°±0.10°, 13.05°±0.10°, 16.58°±0.10°, 18.01°±0.10°, 18.59°±0.10°, 19.70°±0.10°, 19.91°±0.10°, 20.14°±0.10°, 22.01°±0.10°, 23.56°±0.10°, 23.93°±0.10°, 24.78°±0.10° and 26.39°±0.10°.

In a further embodiment, the crystalline form of compound (I) is Form F that exhibits an X-ray powder diffraction (XRPD) pattern shown in FIG. 15.

In a further embodiment, the crystalline Form F is a mono maleic salt of compound (I).

In another aspect, provided herein is a pharmaceutical composition comprising the crystalline form disclosed herein; and a pharmaceutically acceptable carrier, excipient, diluent, adjuvant, vehicle or a combination thereof.

In another aspect, provided herein is the use of the amorphous or crystalline form disclosed herein or the pharmaceutical composition for the manufacture of a medicament for the treatment or prophylaxis of a viral disease in a patient.

In another aspect, the viral disease disclosed herein is respiratory syncytial virus infection or a disease caused by respiratory syncytial virus infection.

In another aspect, provided herein is a method for the treatment or prophylaxis of respiratory syncytial virus infection or a disease caused by respiratory syncytial virus infection, which method comprises administering a therapeutically effective amount of the crystalline form or the pharmaceutical composition disclosed herein.

ABBREVIATIONS

-   -   DSC Differential scanning calorimetry     -   DVS Dynamic vapor sorption     -   Pos. Position     -   Rel. Int. Relative Intensity     -   TGA Thermal gravimetric analysis     -   XRPD X-ray powder diffraction     -   SGF Simulated Gastric Fluid     -   FaSSIF Fasted State Simulated Intestinal Fluid     -   FeSSIF Fed State Simulated Intestinal Fluid

DESCRIPTION OF THE FIGURES

FIG. 1 X-ray powder diffraction pattern for Form A

FIG. 2 DSC thermogram of Form A

FIG. 3 TGA diagram of Form A

FIG. 4 X-ray powder diffraction pattern for Form B

FIG. 5 DSC thermogram of Form B

FIG. 6 TGA diagram of Form B

FIG. 7 X-ray powder diffraction pattern for Form C

FIG. 8 DSC thermogram of Form C

FIG. 9 TGA diagram of Form C

FIG. 10 X-ray crystal structure of Form C

FIG. 11 X-ray powder diffraction pattern for Form D

FIG. 12 DSC thermogram of Form D

FIG. 13 TGA diagram of Form D

FIG. 14 X-ray powder diffraction pattern for mono acetate salt Form E

FIG. 15 X-ray powder diffraction pattern for mono maleic salt Form F

FIG. 16 DVS isotherm of Form A

FIG. 17 DVS isotherm of Form C

FIG. 18 DVS isotherm of Form D

FIG. 19 DVS isotherm of mono acetate salt Form E

FIG. 20 DVS isotherm of mono maleic salt Form F

EXAMPLES

The invention will be more fully understood by reference to the following examples. They should not, however, be construed as limiting the scope of the invention.

HPLC Method for Chemical Purity and Assay Test

HPLC condition is disclosed here in Table 1-1.

TABLE 1-1 HPLC conditions for chemical purity and assay test Instrument Agilent 1200 series HPLC system with DAD detector Column Waters Xbridge Shield RP18(150 × 4.6 mm, 3.5 μm) Oven temperature 40° C. Mobile phase A: 0.1% NH₃•H₂O in water B: 0.1% NH₃•H₂O in Acetonitrile Time (min) A % B % Gradient program 0.00 88 12 2.00 65 35 10.00 55 45 20.00 0 100 23.00 0 100 23.01 88 12 28.00 88 12 Flow rate 0.8 mL/min Detector UV 238 nm Injection Volume 10 μL Diluent Acetonitrile:Water = 1:1, v/v

Example 1

Preparation of Form A of Compound (I)

100 mg of amorphous compound (I) was weighed and transferred into a solvent mixture (MeOH:H₂O (1:5)). Then the precipitation was collected by filtration and the collected solid was thoroughly washed with water and dried under vacuum to get a white solid as Form A.

Form A was analysed using XRPD. The XRPD pattern is shown in FIG. 1. Major peaks and their related intensities in the XRPD pattern are shown in Table 1.

Experimental Conditions:

XRPD: For crystalline form analysis, sample was mounted in a sample holder on a goniometer and measured at ambient conditions. Data were collected at 2-theta from 4 to 40° with a step size of 0.05° and a scanning speed of is/step on a Bruker D8 Advance X-ray powder diffractometer at 40 KV and 40 mA. Cu-radiation of 1.54 Å wavelength was used for data collection.

DSC analysis: DSC curves were recorded using a TA differential scanning calorimeter Q2000. The sample was heated from 25° C. to 350° C. at a rate of 10° C./min.

TGA analysis: The thermogravimetric analysis was operated on TA Q5000. The sample was heated from 120° C. to 400° C. at a rate of 10° C./min.

TABLE 1 X-Ray Powder Diffraction peaks of Form A of compound (I) Pos. [°2 Th.] Height [cts] d-spacing [Å] Rel. Int. [%] 6.46 454 13.6799 9.9 8.37 282 10.5505 6.1 9.79 1219 9.0291 26.5 10.64 856 8.3119 18.6 12.91 241 6.8499 5.2 16.79 4595 5.2750 100.0 17.51 539 5.0602 11.7 18.15 275 4.8842 6.0 19.65 371 4.5147 8.1 20.12 524 4.4109 11.4 21.62 676 4.1072 14.7 23.34 221 3.8079 4.8 25.79 485 3.4515 10.6

DSC and TGA results shown in FIG. 2 and FIG. 3 indicate Form A of compound (I) has an onset melting temperature at 225.3° C.

Example 2

Preparation of Hydrate Form, Form B of Compound (I)

Form B was formed by using Form A as prepared in Example 1 to form a slurry in water at room temperature in 60 hours, then the solid was collected by filtration and dried under vacuum. Form B was characterized by XRPD shown in FIG. 4. Major peaks and their related intensities in the XRPD pattern are shown in Table 2.

Experimental Condition:

XRPD: For crystalline form analysis, sample was mounted in a sample holder on a goniometer and measured at ambient conditions. Data were collected at 2-theta from 4 to 40° with a step size of 0.05° and a scanning speed of is/step on a Bruker D8 Advance X-ray powder diffractometer at 40 KV and 40 mA. Cu-radiation of 1.54 Å wavelength was used for data collection.

DSC analysis: DSC curves were recorded using a TA differential scanning calorimeter Q2000. The sample was heated from 25° C. to 300° C. at a rate of 10° C./min.

TGA analysis: The thermogravimetric analysis was operated on TA Q5000. The sample was heated from 25° C. to 350° C. at a rate of 10° C./min.

TABLE 2 X-Ray Powder Diffraction peaks of Form B of compound (I) Pos. [°2 Th.] Height [cts] d-spacing [Å] Rel. Int. [%] 10.21 339 8.6608 100.0 11.93 294 7.4107 86.7 13.22 193 6.6916 56.9 14.35 282 6.1670 83.2 15.02 145 5.8944 42.8 16.31 146 5.4308 43.1 17.66 155 5.0181 45.7 18.56 258 4.7767 76.1 20.06 128 4.4233 37.8 20.79 217 4.2687 64.0 21.42 143 4.1445 42.2 23.24 220 3.8243 64.9 25.15 243 3.5386 71.7 26.21 160 3.3979 47.2 26.74 190 3.3317 56.0 29.44 121 3.0316 35.7

DSC and TGA results shown in FIG. 5 and FIG. 6 indicate Form B of compound (I) has an dehydration temperature at 57.2° C. and onset melting temperature at 256.3° C.

Example 3

Preparation of Form C of Compound (I)

Form A of compound (I) as prepared in Example 1 was heated to 230° C. and kept at 230° C. for 5 minute under vacuum. The solid was obtained as Form C and characterized by)(RFD, DSC and TGA.

The XRPD pattern of Form C of compound (I) is shown in FIG. 7. Major peaks and their related intensities in the XRPD pattern are shown in Table 3 below.

Experimental Conditions:

XRPD: For crystalline form analysis, sample was mounted in a sample holder on a goniometer and measured at ambient conditions. Data were collected at 2-theta from 4 to 40° with a step size of 0.05° and a scanning speed of is/step on a Bruker D8 Advance X-ray powder diffractometer at 40 KV and 40 mA. Cu-radiation of 1.54 Å wavelength was used for data collection.

DSC analysis: DSC curves were recorded using a TA differential scanning calorimeter Q2000. The sample was heated from 25° C. to 300° C. at a rate of 10° C./min.

TGA analysis: The thermogravimetric analysis was operated on TA Q5000. The sample was heated from 25° C. to 400° C. at a rate of 10° C./min.

TABLE 3 X-Ray Powder Diffraction peaks of Form C of compound (I) Pos. [°2 Th.] Height [cts] d-spacing [Å] Rel. Int. [%] 8.41 2879 10.5099 100.0 8.70 221 10.1579 7.7 10.18 258 8.6791 9.0 10.98 223 8.0502 7.8 12.62 278 7.0088 9.7 13.71 755 6.4531 26.2 14.95 788 5.9210 27.4 15.58 256 5.6830 8.9 16.55 160 5.3534 5.5 17.01 523 5.2090 18.2 17.43 142 5.0844 4.9 19.21 954 4.6159 33.1 20.49 1024 4.3302 35.6 20.83 858 4.2611 29.8 21.46 433 4.1375 15.1 21.69 1031 4.0939 35.8 21.99 1287 4.0398 44.7 22.13 1315 4.0133 45.7 22.55 212 3.9395 7.4 24.29 186 3.6607 6.5 24.67 158 3.6055 5.5 24.95 352 3.5667 12.2 25.30 245 3.5171 8.5 25.85 405 3.4441 14.1 26.31 241 3.3847 8.4 26.63 648 3.3453 22.5 27.34 549 3.2596 19.1 28.01 92 3.1829 3.2 29.23 103 3.0530 3.6 29.92 282 2.9838 9.8 30.26 120 2.9515 4.2 30.74 83 2.9062 2.9 31.04 160 2.8793 5.5 31.87 193 2.8053 6.7 32.46 81 2.7559 2.8 32.78 101 2.7301 3.5 32.99 173 2.7132 6.0 33.95 114 2.6382 4.0 34.46 155 2.6008 5.4

DSC and TGA results shown in FIG. 8 and FIG. 9 indicate Form C of compound (I) has an onset melting temperature at 256.6° C.

FIG. 10 shows the X-ray structure of Form C of compound (I). The single crystal X-ray intensity data were collected at 293K using a Bruker APEX-II CCD diffractometer (Cu-Kα radiation, λ=1.54178 Å). The crystal data and structure refinement is shown in Table 4.

TABLE 4 Crystal data and structure refinement of Form C of compound (I) Empirical formula C₂₂H₂₅N₅O₃S Formula weight 439.53 Temperature 293(2) K Wavelength 0.70000 Å Crystal system, space group Triclinic, P-1 Unit cell dimensions a = 9.2050(18) Å b = 11.036(2) Å c = 11.342(2) Å Alpha = 73.14(3) deg. Beta = 70.23(3) deg. Gamma = 87.61(3) deg. Volume 1035.7(4) Å³ Z, Calculated density 2, 1.409 mg/mm³ Absorption coefficient 0.192 mm⁻¹ F(000) 464 Crystal size 0.2 × 0.10 × 0.02 mm Theta range for data 1.93 to 26.37 deg. collection Limiting indices −11 ≤ h ≤ 11 −13 ≤ k ≤ 13 −14 ≤ l ≤ 14 Reflections 11747/3795[R(int) = 0.0243] collected/unique Completeness to 89.3% theta = 26.37 Absorption correction None Refinement method Full matrix least squares on F² Data/restraints/parameters 3795/0/294 Goodness-of-fit on F²  1.120 Final R indices R1 = 0.0631 [I > 2sigma(I)] wR2 = 0.1590 R indices (all data) R1 = 0.0633 wR2 = 0.1593 Largest diff peak and hole 0.514 and −0.584 e · A⁻³

Example 4

Preparation of Form D of Compound (I)

Form B of compound (I) as prepared in Example 2 was heated to 60° C. and kept at 60° C. for 2 hours. The solid was obtained as Form D and characterized by XRPD, DSC and TGA.

The XRPD pattern of Form D of compound (I) is shown in FIG. 11. Major peaks and their related intensities in the XRPD pattern are shown in Table 5.

Experimental Conditions:

XRPD: For crystalline form analysis, sample was mounted in a sample holder on a goniometer and measured at ambient conditions. Data were collected at 2-theta from 4 to 40° with a step size of 0.05° and a scanning speed of is/step on a Bruker D8 Advance X-ray powder diffractometer at 40 KV and 40 mA. Cu-radiation of 1.54 Å wavelength was used for data collection.

DSC analysis: DSC curves were recorded using a TA differential scanning calorimeter Q2000. The sample was heated from 25° C. to 300° C. at a rate of 10° C./min.

TGA analysis: The thermogravimetric analysis was operated on TA Q5000. The sample was heated from 25° C. to 350° C. at a rate of 10° C./min.

TABLE 5 X-Ray Powder Diffraction peaks of Form D of compound (I) Pos. [°2 Th.] Height [cts] d-spacing [Å] Rel. Int. [%] 7.79 312 11.3383 29.6 10.18 395 8.6790 37.5 11.15 284 7.9313 26.9 12.40 1053 7.1315 100 12.90 200 6.8584 19 13.48 140 6.5627 13.3 15.85 170 5.5887 16.2 16.57 108 5.3443 10.3 16.95 163 5.2256 15.5 17.25 152 5.1378 14.5 18.68 722 4.7475 68.5 19.73 264 4.4970 25.1 20.16 211 4.4004 20 20.43 310 4.3444 29.5 21.16 209 4.1962 19.9 23.14 193 3.8407 18.4 23.93 223 3.7160 21.2 24.83 278 3.5826 26.4 25.71 259 3.4626 24.6 26.44 135 3.3687 12.8 27.11 213 3.2868 20.2 28.68 163 3.1097 15.5 32.51 186 2.7522 17.7 39.10 94 2.3019 8.9

DSC and TGA results shown in FIG. 12 and FIG. 13 indicate Form D of compound (I) has an dehydration temperature at 53.2° C. and onset melting temperature at 255.6° C.

Example 5

Preparation of Mono Acetate Salt Form E of Compound (I)

44 mg of Form C of compound (I) as prepared in Example 3 was dissolved in 440 μL ethyl acetate. Equal molar acetic acid was added to previous reaction mixture. The mixture was stirred at room temperature overnight to generate precipitation. The solid was isolated as Form E for XRPD analysis.

The XRPD pattern of mono acetate salt Form E of compound (I) is shown in FIG. 14. Major peaks and their related intensities in the XRPD pattern are shown in Table 6.

Experimental Conditions:

XRPD: For crystalline form analysis, sample was mounted in a sample holder on a goniometer and measured at ambient conditions. Data were collected at 2-theta from 4 to 40° with a step size of 0.05° and a scanning speed of is/step on a Bruker D8 Advance X-ray powder diffractometer at 40 KV and 40 mA. Cu-radiation of 1.54 Å wavelength was used for data collection.

TABLE 6 X-Ray Powder Diffraction peaks of mono acetate salt Form E of compound (I) Pos. [°2 Th.] Height [cts] d-spacing [Å] Rel. Int. [%] 5.96 2044 14.82996 23.1 8.32 8852 10.61968 100.0 9.34 1956 9.4603 22.1 11.82 1647 7.4798 18.6 13.22 750 6.6902 8.5 15.09 1691 5.8660 19.1 16.90 1088 5.2417 12.3 17.46 1103 5.0764 12.5 17.81 721 4.9773 8.1 18.42 529 4.8130 6.0 19.44 1485 4.5623 16.8 19.88 471 4.4628 5.3 20.78 676 4.2705 7.6 21.08 956 4.2120 10.8 22.59 1323 3.9323 15.0 23.12 1162 3.8441 13.1 23.53 573 3.7783 6.5 23.88 603 3.7237 6.8 25.25 1088 3.5244 12.3 25.60 1706 3.4769 19.3 26.65 515 3.3422 5.8 28.34 1250 3.1463 14.1 30.74 382 2.9065 4.3

Example 6

Preparation of Mono Maleic Salt Form F of Compound (I)

44 mg of Form C of compound (I) as prepared in Example 3 was dissolved in 440 μL ethanol. Equal molar maleic acid was added to previous reaction mixture. The mixture was stirred at room temperature overnight to generate precipitation. The solid was isolated as Form F for XRPD analysis.

The XRPD pattern of mono maleic salt Form F of compound (I) is shown in FIG. 15. Major peaks and their related intensities in the XRPD pattern are shown in Table 7.

Experimental Conditions:

XRPD: For crystalline form analysis, sample was mounted in a sample holder on a goniometer and measured at ambient conditions. Data were collected at 2-theta from 4 to 40° with a step size of 0.05° and a scanning speed of is/step on a Bruker D8 Advance X-ray powder diffractometer at 40 KV and 40 mA. Cu-radiation of 1.54 Å wavelength was used for data collection.

TABLE 7 X-Ray Powder Diffraction peaks of mono maleic salt Form F of compound (I) Pos. [°2 Th.] Height [cts] d-spacing [Å] Rel. Int. [%] 8.32 515 10.6204 22.1 10.27 2329 8.6028 100.0 11.53 379 7.6690 16.3 12.38 983 7.1463 42.2 13.05 735 6.7801 31.6 13.78 170 6.4226 7.3 14.62 286 6.0526 12.3 16.58 696 5.3428 29.9 17.31 441 5.1192 18.9 18.01 484 4.9216 20.8 18.59 836 4.7684 35.9 19.00 267 4.6667 11.5 19.32 341 4.5899 14.6 19.70 619 4.5024 26.6 19.91 1250 4.4566 53.7 20.14 1412 4.4055 60.6 21.28 224 4.1723 9.6 22.01 580 4.0356 24.9 23.15 333 3.8396 14.3 23.56 588 3.7739 25.2 23.93 836 3.7149 35.9 24.78 921 3.5899 39.5 26.39 499 3.3750 21.4 27.09 480 3.2893 20.6 27.76 248 3.2113 10.6 28.84 364 3.0934 15.6 29.54 279 3.0216 12.0 29.92 174 2.9842 7.5 30.53 201 2.9256 8.6 32.17 186 2.7806 8.0 32.81 221 2.7276 9.5 33.63 163 2.6632 7.0 34.94 190 2.5660 8.1

Example 7

Hygroscopicity of Crystal Forms

Dynamic vapour sorption (DVS) was tested using a DVS intrinsic from SMS (Surface Measurement Systems Co. Ltd.). 20 mg compound (I) of each crystal form was placed in an aluminium sample pan and recorded the sample weight change under different humidity. The DVS method parameters were set according to Table 16, and the method was run by the machine based on such parameters.

The hygroscopicity results of different crystal forms are shown in Table 17. According to the hygroscopicity results, the Form A, C, E and F of compound (I) showed much improved hygroscopicity than Form D.

TABLE 16 The testing parameters of DVS Parameters Value Temperature 25° C. Sample size 10-20 mg Gas and flow rate N₂, 200 mL/min dm/dt 0.002%/min Min. dm/dt stability duration  10 min Max. equilibrium time 180 min RH range 0% RH-95% RH-0% RH RH step size 5% (0% RH-95% RH-0% RH)

TABLE 17 The results of hygroscopicity test. Samples Hygroscopicity FIG. No. Example 1, Form A of 0.25% water sorption @80% RH FIG. 16 compound (I) Example 3, Form C of 0.04% water sorption @80% RH FIG. 17 compound (I) Example 4, Form D of 7.52% water sorption @80% RH FIG. 18 compound (I) Example 5, Form E of 1.12% water sorption @80% RH FIG. 19 compound (I) Example 6, Form F of 0.50% water sorption @80% RH FIG. 20 compound (I)

Example 8

Chemical Stability of Crystal Forms

40 mg compound (I) of crystal Forms C, E and F were stored in stability chamber with temperature and humidity controlled as 50° C. and 40° C./75% RH respectively, 40 mg compound (I) of Form B was stored at 105° C. oven. After each time point, the samples were analyzed by HPLC to check their chemical purity and compared with their initial value. According to the results shown in Table 18, all crystal forms of compound (I) showed good chemical stability properties.

TABLE 18 Chemical stability data of different crystal forms of compound (I) Chemical Samples Conditions Time point Purity, % Example 2, Form B of — Initial 99.81% compound (I) 105° C.  24 hr 99.80% Example 3, Form C of — Initial 99.30% compound (I) 50° C.  1 month 99.32% 40° C./75% RH 99.28% Example 5, Form E of — Initial 99.49% compound (I) 50° C.  1 month 99.45% 40° C./75% RH 99.14% Example 6, Form F of — Initial 99.62% compound (I) 50° C.  1 month 99.43% 40° C./75% RH 99.42%

Example 9

Equilibrium Aqueous Solubility

Aqueous solubility was determined by suspending 10 mg compound in different bio-relevant media including SGF, FaSSIF and FeSSIF. The suspension was equilibrated at 25° C. for 24 hours then the final pH was measured. The suspension was then filtered through a 0.22 um PVDF filter into a 2-mL HPLC vial. The quantitation was conducted by HPLC (described in Example 10) with reference to a standard solution. The solubility results of selected novel crystal forms in this invention are shown in Table 19 which showed good aqueous solubility higher than 0.1 mg/mL.

TABLE 19 Aqueous solubility of different crystal forms SGF FaSSIF FeSSIF Samples S, mg/mL Final pH S, mg/mL Final pH S, mg/mL Final pH Example 1, Form A of 2.40 4.80 0.12 6.60 1.72 5.31 compound (I) Example 3, Form C of 3.81 4.92 0.11 6.63 1.88 5.26 compound (I) Example 5, Form E of >5 4.69 0.90 5.31 2.18 5.34 compound (I) Example 6, Form F of >5 3.15 1.58 4.99 1.99 5.18 compound (I) 

The invention claimed is:
 1. A method for the treatment or prophylaxis of respiratory syncytial virus infection or a disease caused by respiratory syncytial virus infection, which method comprises administering a therapeutically effective amount of the crystalline form of the compound of formula (I):

or a salt, solvent or combination of salts and solvates thereof; wherein the crystalline form is Form A, Form B, Form C, Form D, Form E or Form F, or a combination thereof.
 2. The method of claim 1, wherein the crystalline form is Form A that exhibits an X-ray powder diffraction (XRPD) pattern with characteristic peaks expressed in degrees 2-theta at 9.79°±0.10°, 10.64°±0.10°, 16.79°±0.10°, 17.51°±0.10°, 20.12°±0.10°, 21.62°±0.10° and 25.79°±0.10°.
 3. The method of claim 2, wherein the crystalline form is Form A that exhibits an X-ray powder diffraction (XRPD) pattern with characteristic peaks expressed in degrees 2-theta at 6.46°±0.10°, 8.37°±0.10°, 9.79°±0.10°, 10.64°±0.10°, 12.91°±0.10°, 16.79°±0.10°, 17.51°±0.10°, 18.15°±0.10°, 19.65°±0.10°, 20.12°±0.10°, 21.62°±0.10°, 23.34°±0.10° and 25.79°±0.10°.
 4. The method of claim 2, wherein the crystalline form is Form A that exhibits an X-ray powder diffraction (XRPD) pattern shown in FIG.
 1. 5. The method of claim 1, wherein the crystalline form is Form B that exhibits an X-ray powder diffraction (XRPD) pattern with characteristic peaks expressed in degrees 2-theta at 10.21°±0.10°, 11.93°±0.10°, 13.22°±0.10°, 14.35°±0.10°, 18.56°±0.10°, 20.79°±0.10°, 23.24°±0.10° and 25.15°±0.10°.
 6. The method of claim 5, wherein the crystalline form is Form B that exhibits an X-ray powder diffraction (XRPD) pattern with characteristic peaks expressed in degrees 2-theta at 10.21°±0.10°, 11.93°±0.10°, 13.22°±0.10°, 14.35°±0.10°, 15.02°±0.10°, 16.31°±0.10°, 17.66°±0.10°, 18.56°±0.10°, 20.06°±0.10°, 20.79°±0.10°, 21.42°±0.10°, 23.24°±0.10°, 25.15°±0.10°, 26.21°±0.10°, 26.74°±0.10° and 29.44°±0.10°.
 7. The method of claim 5, wherein the crystalline form is Form B that exhibits an X-ray powder diffraction (XRPD) pattern shown in FIG.
 4. 8. The method of claim 1, wherein the crystalline Form B is a hydrate of compound (I).
 9. The method of claim 1, wherein the crystalline form is Form C that exhibits an X-ray powder diffraction (XRPD) pattern with characteristic peaks expressed in degrees 2-theta at 8.41°±0.10°, 19.21°±0.10°, 20.49°±0.10°, 20.83°±0.10°, 21.69°±0.10°, 21.99°±0.10° and 22.13°±0.10°.
 10. The method of claim 9, wherein the crystalline form is Form C that exhibits an X-ray powder diffraction (XRPD) pattern with characteristic peaks expressed in degrees 2-theta at 8.41°±0.10°, 13.71°±0.10°, 14.95°±0.10°, 17.01°±0.10°, 19.21°±0.10°, 20.49°±0.10°, 20.83°±0.10°, 21.46°±0.10°, 21.69°±0.10°, 21.99°±0.10°, 22.13°±0.10°, 24.95°±0.10°, 25.85°±0.10°, 26.63°±0.10° and 27.34°±0.10°.
 11. The method of claim 9, wherein the crystalline form is Form C that exhibits an X-ray powder diffraction (XRPD) pattern shown in FIG.
 7. 12. The method of claim 1, wherein the crystalline form is Form D that exhibits an X-ray powder diffraction (XRPD) pattern with characteristic peaks expressed in degrees 2-theta at 7.79°±0.10°, 10.18°±0.10°, 11.15°±0.10°, 12.40°±0.10°, 18.68°±0.10°, 20.43°±0.10° and 24.83°±0.10°.
 13. The method of claim 12, wherein the crystalline form is Form D that exhibits an X-ray powder diffraction (XRPD) pattern with characteristic peaks expressed in degrees 2-theta at 7.79°±0.10°, 10.18°±0.10°, 11.15°±0.10°, 12.40°±0.10°, 12.90°±0.10°, 18.68°±0.10°, 19.73°±0.10°, 20.16°±0.10°, 20.43°±0.10°, 21.16°±0.10°, 23.14°±0.10°, 23.93°±0.10°, 24.83°±0.10°, 25.71°±0.10° and 27.11°±0.10°.
 14. The method of claim 12, wherein the crystalline form is Form D that exhibits an X-ray powder diffraction (XRPD) pattern shown in FIG.
 11. 15. The method of claim 1, wherein the crystalline form is Form E that exhibits an X-ray powder diffraction (XRPD) pattern with characteristic peaks expressed in degrees 2-theta at 5.96°±0.10°, 8.32°±0.10°, 9.34°±0.10°, 11.82°±0.10°, 15.09°±0.10°, 19.44°±0.10° and 25.60°±0.10°.
 16. The method of claim 15, wherein the crystalline form is Form E that exhibits an X-ray powder diffraction (XRPD) pattern with characteristic peaks expressed in degrees 2-theta at 5.96°±0.10°, 8.32°±0.10°, 9.34°±0.10°, 11.82°±0.10°, 13.22°±0.10°, 15.09°±0.10°, 16.90°±0.10°, 17.46°±0.10°, 19.44°±0.10°, 21.08°±0.10°, 22.59°±0.10°, 23.12°±0.10°, 25.25°±0.10°, 25.60°±0.10° and 28.34°±0.10°.
 17. The method of claim 15, wherein the crystalline form is Form E that exhibits an X-ray powder diffraction (XRPD) pattern shown in FIG.
 14. 18. The method of claim 15, wherein the crystalline Form E is a mono acetate salt of compound (I).
 19. The method of claim 1, wherein the crystalline form is Form F that exhibits an X-ray powder diffraction (XRPD) pattern with characteristic peaks expressed in degrees 2-theta at 10.27°±0.10°, 12.38°±0.10°, 18.59°±0.10°, 19.91°±0.10°, 20.14°±0.10°, 23.93°±0.10° and 24.78°±0.10°.
 20. The method of claim 19, wherein the crystalline form is Form F that exhibits an X-ray powder diffraction (XRPD) pattern with characteristic peaks expressed in degrees 2-theta at 8.32°±0.10°, 10.27°±0.10°, 12.38°±0.10°, 13.05°±0.10°, 16.58°±0.10°, 18.01°±0.10°, 18.59°±0.10°, 19.70°±0.10°, 19.91°±0.10°, 20.14°±0.10°, 22.01°±0.10°, 23.56°±0.10°, 23.93°±0.10°, 24.78°±0.10° and 26.39°±0.10°.
 21. The method of claim 19, wherein the crystalline form is Form F that exhibits an X-ray powder diffraction (XRPD) pattern shown in FIG.
 15. 22. The method of claim 1, wherein the crystalline Form F is a mono maleic salt of compound (I). 